In conventional laryngoscopes, the blade has a light bulb serving as a light source and the light bulb is located near the outer end of the blade. This light bulb is housed in a cylindrical part which projects laterally and outwardly of the outer surface of the blade, thereby adding to the maximum transverse dimension of the blade, an undesirable feature in itself. The light bulb is electrically connected by a conductor wire and by the metallic base of the blade to a battery in the handle of the laryngoscope when the handle is coupled to the base of the blade, the handle being separable from the base of the blade. The conductor wire sometimes becomes detached from the light bulb for one reason or another and this requires repair of the connection between the wire and the light bulb before the laryngoscope can be properly used again.
The wire is usually carried in a rigid conduit secured to the outer side of the blade and extending from the base along the blade to the outer end of the blade. This conduit further adds to the maximum transverse dimension of the blade. Also, the presence of moisture, such as saliva, in and around the connection between the conductor wire and the light bulb has an adverse effect on the operation of the bulb.
Because of the foregoing problems, a need has arisen for a laryngoscope with an improved light source, one which will have high reliability and will not require the need for a new design for the handle of the laryngoscope while keeping the transverse dimensions of the blade to a minimum.